This invention relates to a lubrication system for a device, such as a centrifugal chemical processing pump, employing a rotating shaft with corresponding shaft supporting bearings. More particularly, this invention relates to a lubrication system for lubricating shaft supporting bearings, the system including a lubricant dispenser affixed to the shaft for rotation therewith and wherein the dispenser includes a plurality of pivotally mounted members for dispensing lubricant toward the bearings.
This application is related to U.S. Pat. No. 5,647,735, issued Jul. 15, 1997, the disclosures of which is hereby incorporated herein by reference.
Environmentally hazardous fluids, such as acids, oils, and toxins, often need to be pumped throughout fluid flow systems from one location to another. Centrifugal chemical processing pumps including a motor driven impeller affixed to a pump shaft are typically utilized in pumping such fluids. See, for example, U.S. Pat. No. 5,411,366, the disclosure of which is hereby incorporated herein by reference.
The shafts of such pumps are typically rotatably supported against radial movement and vibration by conventional pump shaft bearings (e.g. ball bearings). These bearings must be continually lubricated throughout the operation of the pump in order to reduce maintenance requirements and maintain a satisfactory operating life of the bearings and thus the pump.
Conventional lubricating fluid, such as oil, is typically used to lubricate such pump shaft bearings. Conventional chemical processing pumps typically include ball bearings for supporting the pump shaft, the bearings being disposed within a misting or lubrication chamber. In the prior art, these shaft supporting ball bearings are typically lubricated by positioning the oil level within the lubrication chamber at a level or position about half-way up the bottom ball of the bearing. Maintaining the lubricating oil at such a position necessarily means that when the shaft and supporting bearings are rotated, the bearings must continuously plow through the lubricating oil in which they are partially submerged. This results in undesirable heat generation within the bearings and adjacent to pump shaft, such heat being caused by the friction created by the bearings continually passing through the lubricating oil. Such heat generation increases maintenance requirements and reduces the operating life of the bearings.
If the oil level could be lowered, less heat would be generated. However, a lower oil level requires a dispenser having a larger outer diameter. Next is the issue of how to get the bearing lubrication system (including a large rotating dispenser) into the misting or lubricating chamber adjacent the bearings. Typically, it is desirable to slide the lubricant dispenser into the misting chamber along with the shaft and bearings through a hole or bore in the body of the pump. Thus, in the past, the size (i.e. outer diameter) of the lubricant dispenser, which could be inserted into the misting chamber in such a manner, has been limited by the diameter of the hole or bore in the pump. In other words, one could not insert a lubricant dispenser into the misting chamber if the outer diameter of the dispenser was greater than the interior diameter of the bore existing in the pump body.
Conventional systems also fail to efficiently and effectively distribute oil through centrifugally-operated rotating equipment because such systems create unwanted splashing and spraying of excessive lubricant into or away from the bearings that require lubrication.
It is apparent from the above that there exists a need in the art for a lubricant dispenser, which may be inserted into rotating equipment (e.g. chemical processing pump) wherein the outer diameter of the lubricant dispenser during operation is greater than the inner diameter of the space in the pump through which the dispenser must be inserted. It is also a purpose of this invention to provide a lubrication system wherein the fluid is maintained at a level below the bearings disposed in the chamber so as to reduce or eliminate heat generation caused by the bearings plowing through and being submerged in a lubricating fluid. The lower lubricant level necessitates a larger dispenser according to certain embodiments.
It is the purpose of this invention to fulfill the above-described needs in the art, as well as other needs apparent to the skilled artisan from the following detailed description of this invention.
It is the object of this invention to provide a lubricant dispenser, which may be inserted into rotating equipment (e.g. chemical processing pump) wherein the outer diameter of the lubricant dispenser during operation is greater than the inner diameter of the space in the pump body through which the dispenser must be inserted.
It is also an object of this invention to provide a lubrication system wherein the fluid is maintained at a level below the bearings disposed in the chamber so as to reduce heat generation caused by the bearings rotating through and being submerged in a lubricating fluid.
It is also an object of this invention to provide a lubrication system that reduces a splashing effect of the lubrication dispenser when the dispenser members contact the lubricant.
Generally speaking, this invention fulfills the above-described needs in the art by providing a centrifugal pump for pumping a liquid to be pumped, the pump comprising:
a pump housing;
a rotatable shaft disposed at least partially within said housing;
a lubrication chamber surrounding the shaft, the chamber for housing a lubricating fluid;
shaft supporting bearings disposed in or adjacent the lubrication chamber, the bearings to be lubricated by the lubricating fluid;
a dispenser including a base support member and a plurality of collapsible dispensing members pivotally attached thereto, the dispenser being attached to the shaft for rotation therewith and for dispensing the lubricating fluid in the chamber in order to lubricate the bearings; and
wherein the collapsible dispensing members designed with a profiled oil-engaging edge that reduces splashing or spraying of the oil.
According to another aspect of the invention, the pivoting mechanism related to the collapsible dispensing members has been improved to increase strength and reduce frictional resistance, thereby increasing the operating life of the bearings and oil dispensing system associated therewith.
According to a further aspect of the invention, the dispensing blades are formed with a selective height chosen according to the particular pump system to which the dispenser is attached.
Each aspect of the invention provides a dispensing system that improves distribution of lubrication and increases the operating life of the dispenser and bearings.
This invention will now be described with respect to certain embodiments thereof, accompanied by certain illustrations that follow.